Skateboard with variable-rate elastomeric steering control spring

ABSTRACT

A skateboard and a variable-rate elastomeric steering control spring include a boardside unitary body formed of an exterior first elastomer having a first durometer on the Shore “A” scale, and an interior second elastomer coupled to the first elastomer and extending at least length of the exterior first elastomer, the second elastomer having a second durometer on the Shore “A” scale and a through hole disposed to receive a kingpin of the skate truck; a roadside unitary body formed of an exterior third elastomer having a third durometer on the Shore “A” scale, and an interior fourth elastomer coupled to the third elastomer and extending at least a length of the exterior third elastomer, the interior fourth elastomer having a fourth durometer on the Shore “A” scale and a through hole disposed to receive the kingpin; and wherein the first, second, third and fourth elastomers comprise at least two durometers on the Shore “A” scale between 65 A and 100 A to enable the boardside unitary body and the roadside unitary body to form the variable-rate elastomeric steering control spring when disposed on the kingpin of the skate truck.

CROSS-REFERENCE TO RELATED APPLICATION

This is a continuation-in-part of co-pending U.S. patent applicationSer. No. 15/215,596, titled “SHOCK-ABSORBING BUSHING OF SKATEBOARD”filed on Jul. 21, 2016, which is hereby incorporated by reference in itsentirety.

FIELD OF INVENTION

This invention relates generally to the field of skateboards andskateboard assemblies.

BACKGROUND INFORMATION

A skateboard is a carrying structure. Competition-level skateboardingincludes bowl riding, freestyle, slalom racing, streetstyle, ramp ridingand downhill racing. Advanced skaters have performance requirementsreflected in the assemblies of the trucks and other component parts of askateboard. Advanced skaters and novice skaters alike may executevarious difficult moves or actions, such as turning in air, for purposesof exhibition or competition.

The most commonly known skateboard structure includes a board with twoskate trucks with baseplates mounted to an underside and each of thebaseplates having a kingpin mounted thereto to support an axle hanger sothat the entire structure can support a skater.

The kingpin of the baseplate is often additionally provided with anelastomeric spring, which is also referred to as a bushing in the field.Such an elastomeric spring or bushing absorbs shocks and vibrations andresiliently opposes leaning forces so as to provide steering control andreturn-to-center force at the end of turns.

The conventional skateboard is imperfect with respect to turning controland shock damping. Further improvement is needed.

SUMMARY

An object of the present invention is to provide a steering-controlspring of a skateboard with at least two plastic/elastomeric materialshaving different values of hardness for absorbing an impact force or avibration force and providing finely-tuned steering control.

Embodiments herein provide for a variable-rate elastomeric steeringcontrol spring for a skate truck, including a boardside unitary bodyformed of an exterior first elastomer having a first durometer on theShore “A” scale, and an interior second elastomer coupled to the firstelastomer and extending at least the length of the exterior firstelastomer, the second elastomer having a second durometer on the Shore“A” scale and a through hole disposed to receive a kingpin of the skatetruck, and a roadside unitary body formed of an exterior third elastomerhaving a third durometer on the Shore “A” scale, and an interior fourthelastomer coupled to the third elastomer and extending at least thelength of the exterior third elastomer, the interior fourth elastomerhaving a fourth durometer on the Shore “A” scale and a through holedisposed to receive the kingpin, and wherein the first, second, thirdand fourth elastomers comprise at least two durometers on the Shore “A”scale between 65 A and 100 A to enable the boardside unitary body andthe roadside unitary body to form the variable-rate elastomeric steeringcontrol spring when disposed on the kingpin of the skate truck.

In one embodiment, the variable-rate elastomeric steering control springis part of the skate truck including a seat to receive a distal end ofthe boardside unitary body and a proximal end of the roadside unitarybody and allow for compression of the variable-rate elastomeric steeringcontrol spring.

In one embodiment, the variable-rate elastomeric steering control springhas a boardside unitary body with a cylindrical shape and the roadsideunitary body has a frustrum shape.

In another embodiment, the variable-rate elastomeric steering controlspring has interior elastomers in both the boardside unitary bodies andthe roadside unitary bodies that have shapes with cross-sectionsconsisting of at least one of the following: hourglass, triangular,rectangular, semi-circular, asymmetric, and rhombus.

In one embodiment, the shape of the interior elastomer and exteriorelastomers functionally affect turning control of the skate truck. Inanother embodiment, the boardside and roadside interior elastomer shapesprovide a non-linear steering control profile for the skate truck.

In one embodiment, the variable-rate elastomeric steering control springhas first and third durometers that are between 85 A and 100 A of theShore “A” scale; and the second and fourth durometers are between 65 Aand 90 A of the Shore “A” scale.

In another embodiment, the variable-rate elastomeric steering controlspring has first, second, third and fourth elastomers having fourdifferent durometers of between 65 A and 100 A of the Shore “A” scale.Alternatively, the variable-rate elastomeric steering control spring canhave a boardside unitary body with a fifth elastomer disposed betweenthe first and the second elastomers, the fifth elastomer having adurometer of between 65 A and 100 A of the Shore “A” scale.

In another embodiment, the roadside unitary body has a sixth elastomerdisposed between the third and the fourth elastomers, the sixthelastomer having a durometer of between 65 A and 100 A of the Shore “A”scale.

Another embodiment is directed to a skateboard including a deck, atleast two skate trucks coupled to the deck, each skate truck includingan axle, a mounting bracket including a kingpin protruding down from themounting bracket, the kingpin coupled to a variable-rate elastomericsteering control spring assembly. The variable elastomeric steeringcontrol spring can include a boardside unitary body formed of anexterior first elastomer having a first durometer on the Shore “A”scale, and an interior second elastomer coupled to the first elastomerand extending at least a length of the exterior first elastomer, thesecond elastomer having a second durometer on the Shore “A” scale and athrough hole disposed to receive a kingpin of the skate truck, and aroadside unitary body formed of an exterior third elastomer having athird durometer on the Shore “A” scale, and an interior fourth elastomercoupled to the third elastomer and extending at least a length of theexterior third elastomer, the interior fourth elastomer having a fourthdurometer on the Shore “A” scale and a through hole disposed to receivethe kingpin wherein the first, second, third and fourth elastomers ofthe boardside unitary body and the roadside unitary body form thevariable-rate elastomeric steering control spring when disposed on thekingpin of the skate truck.

In one embodiment, the at least two skate trucks of the skateboardinclude a seat to receive a distal end of the boardside unitary body anda proximal end of the roadside unitary body and allow for compression ofthe variable-rate elastomeric steering control spring.

In another embodiment of the skateboard, the boardside unitary body hasa cylindrical shape and the roadside unitary body has a frustrum shape.

In another embodiment of the skateboard, the interior elastomers of boththe boardside unitary bodies and the roadside unitary bodies have shapeswith cross-sections consisting of at least one of the following shapes:hourglass, triangular, rectangular, circular, asymmetric, and rhombus.

In an embodiment, the shape of the interior elastomer and exteriorelastomers functionally affects the turning control profile of theskateboard. For example, the boardside and roadside interior elastomershape can provide a non-linear resistance profile of the skate truck.

Another embodiment is directed to an apparatus including a roadsideunitary body formed of an exterior elastomer having a durometer on theShore “A” scale of between 65 A and 100 A, and an interior elastomercoupled to the exterior elastomer and extending at least a length of theexterior elastomer, the interior elastomer having a durometer on theShore “A” scale between 65 A and 100 A and a through hole disposed toreceive a kingpin for attaching the roadside unitary body to a skatetruck for a skateboard, wherein the exterior and interior elastomershave at least two durometers on the Shore “A” scale between 65 A and 100A to enable the roadside unitary body to form a variable-rateelastomeric steering control spring when disposed on the kingpin of theskate truck.

In one embodiment of the apparatus, the roadside unitary body isdisposed on the kingpin of the skate truck as part of a variable-rateelastomeric steering control spring, wherein the spring includes: theroadside unitary body, and a boardside unitary body formed of theexterior elastomer and the interior elastomer coupled to the andextending at least a length of the exterior elastomer and having throughhole disposed to receive the kingpin of the skate truck.

In one embodiment, either the roadside unitary body or the boardsideunitary body is disposed on the kingpin of the skate truck and theinterior elastomers of both the boardside unitary bodies and theroadside unitary bodies have shapes with cross-sections consisting of atleast one of the following: hourglass, triangular, rectangular,semi-circular, asymmetric, and rhombus.

Beneficial efficacy of the disclosure herein is that a skateboard thatinvolves the turning control spring of the present invention showssuperiority in respect of steering mobility and control at variousspeeds.

In addition to the foregoing, other method aspects are described in theclaims, drawings, and text forming a part of the present disclosure.

The foregoing summary is illustrative only and is not intended to be inany way limiting. In addition to the illustrative aspects, embodiments,and features described above, further aspects, embodiments, and featureswill become apparent by reference to the drawings and the followingdetailed description.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1A illustrates perspective view of a boardside unitary body inaccordance with an embodiment of the present application.

FIG. 1B illustrates perspective view of a roadside unitary body inaccordance with an embodiment of the present application.

FIG. 2 illustrates an exploded view of a unitary body in accordance withan embodiment of the present application.

FIG. 3 is a cross-sectional implementation of a unitary body inaccordance with an embodiment of the present application.

FIG. 4 illustrates a cross-sectional implementation of a unitary body inaccordance with an alternate embodiment of the present application.

FIG. 5 illustrates a partial view of a skateboard in accordance with anembodiment of the present application.

FIGS. 6A, 6B and 6C illustrate a particular implementation of aboardside unitary body showing interior elastomer with a triangulargeometrically widened area 610 in accordance with an embodiment of thepresent application.

FIGS. 7A, 7B and 7C illustrate a particular implementation of aboardside unitary body showing interior elastomer semi-circular widening710 in accordance with an embodiment of the present application.

FIGS. 8A, 8B and 8C illustrate a particular implementation of roadsideunitary body showing interior elastomer triangular widening 810 inaccordance with an embodiment of the present application.

FIGS. 9A, 9B and 9C illustrate a particular implementation of aboardside unitary body showing interior elastomer semi-circular widening910 in accordance with an embodiment of the present application.

FIGS. 10A, 10B and 10C illustrate a particular implementation of aboardside unitary body showing interior elastomer geometric rhombus-likeasymmetric widening 1010 in accordance with an embodiment of the presentapplication.

FIGS. 11A, 11B and 11C illustrate a particular implementation of aroadside unitary body showing interior elastomer geometric rhombus-likeasymmetric widening 1110 in accordance with an embodiment of the presentapplication.

FIGS. 12A, 12B and 12C illustrate a particular implementation of aroadside unitary body showing interior elastomer geometric rhombus-likeasymmetric widening 1210 in accordance with an embodiment of the presentapplication.

FIGS. 13A, 13B and 13C illustrate a particular implementation of aboardside unitary body showing interior elastomer geometric triangularsymmetric narrowing 1310 in accordance with an embodiment of the presentapplication.

FIGS. 14A, 14B and 14C illustrate a particular implementation of aboardside unitary body showing interior elastomer with an hourglasssymmetric shape 1410 in accordance with an embodiment of the presentapplication.

FIGS. 15A, 15B and 15C illustrate a particular implementation of aroadside unitary body showing another embodiment of triangular narrowedinterior elastomer cross-section area 1510 in accordance with anembodiment of the present application.

FIGS. 16A, 16B and 16C illustrate a particular implementation of aroadside unitary body showing interior elastomer with a dual hourglasssymmetric cross-section area 1610 in accordance with an embodiment ofthe present application.

FIGS. 17A, 17B and 17C illustrate a particular implementation of aboardside unitary body showing partially lengthened interior elastomercross-section area 1710 as compared to the exterior elastomer inaccordance with an embodiment of the present application.

FIGS. 18A, 18B and 18C illustrate a particular implementation of aroadside unitary body showing partially lengthened bottom end interiorelastomer 1810 in accordance with an embodiment of the presentapplication.

FIGS. 19A, 19B and 19C illustrate a particular implementation of aroadside unitary body showing partially lengthened upper end interiorelastomer 1910 in accordance with an embodiment of the presentapplication.

FIGS. 20A, 20B and 20C illustrate an implementation of a boardsideunitary body showing interior elastomer 2010 with rectangularcross-section in accordance with an embodiment of the presentapplication.

FIGS. 21A, 21B and 21C illustrate an implementation of a roadsideunitary body showing interior elastomer 2110 with rectangularcross-section in accordance with an embodiment of the presentapplication.

DETAILED DESCRIPTION

In the following detailed description, reference is made to theaccompanying drawings, which form a part hereof. In the drawings,similar symbols typically identify similar components, unless contextdictates otherwise. The illustrative embodiments described in thedetailed description, drawings, and claims are not meant to be limiting.Other embodiments may be utilized, and other changes may be made,without departing from the spirit or scope of the subject matterpresented here.

The present invention provides an elastic spring, also referred to as a“kingpin,” having at least two elastomers with different durometers.Referring now to FIGS. 1A and 1B, a boardside and a roadside portion ofa spring, respectively, are shown for use with a skateboard. FIG. 2illustrates an exploded view of a boardside unitary body of the springwith the different component durometer elastomers 10 and 20 and hole 11.The at least two component durometers in embodiments herein combine tocreate a unitary body. FIGS. 3 and 4 illustrate cross sections of theboardside unitary body with multiple elastomers having differentdurometers and hole 11 for receiving a kingpin. FIG. 3 illustrates thetwo elastomers, an interior elastomer 10 and an exterior elastomer 20and hole 11 for receiving a kingpin. FIG. 4 illustrates threeelastomers, with two interior elastomers 10 and 20 and an exteriorelastomer 30 and a hole for receiving a kingpin 11 a.

Generally, a skateboard has an underside for attaching skate trucks.Referring to FIG. 5, a portion of a skateboard 500 is shown with deck 90with a skate truck 91. A skateboard 500 includes two skate trucks 91each with an axle hanger 92 mounted with kingpin 511 going through hole11 and separating boardside unitary body 1 and roadside unitary body 1 a

According to an embodiment, the elastic spring shown in FIG. 1A and FIG.1B represent a variable-rate elastomeric steering control kingpinspring. Specifically, spring 1 shown in FIG. 1A includes a boardsideunitary body 1 formed of an exterior first elastomer 20 having a firstdurometer on the Shore “A” scale, and an interior second elastomer 10coupled to the first elastomer 20 and extending a length of the exteriorfirst elastomer 20, the second elastomer 10 having a second durometer onthe Shore “A” scale and a through hole 11 disposed to receive a kingpinin the skate truck.

FIG. 1B illustrates a roadside unitary body 1 a formed of an exteriorthird elastomer 20 a having a third durometer on the Shore “A” scale,and an interior fourth elastomer 10 a coupled to the third elastomer 20a and extending at least a length of the exterior third elastomer 10 a,and the interior fourth elastomer 10 a having a through hole 11 disposedto receive the kingpin.

In an embodiment, the first 20, second 10, third 20 a and fourth 10 aelastomers include at least two durometers on the Shore “A” scalebetween 65 A and 100 A to enable the boardside unitary body and theroadside unitary body to form the variable-rate elastomeric steeringcontrol spring when disposed on the kingpin 511 of a skate truck. In oneembodiment, the skate truck is one of two skate trucks on a skateboard.In another embodiment, the skate trucks are disposed as 4 skate truckson skates.

According to an embodiment, the first, second, third and fourthelastomers can have at least two durometers on the Shore “A” scalebetween 65 A and 100 A to enable the boardside unitary body and theroadside unitary body to form the variable-rate steering control springwhen disposed on the kingpin of the skate truck hanger.

In another embodiment, the first, second, third and fourth elastomershave different durometers such that a interior elastomer “sleeve”portion 10 and 10 a can have a softer or harder durometers as comparedto the exterior portion 20 and 20 a.

In an embodiment, interior first elastomer and interior third elastomer10 and 10 a have a first durometer that is harder than second exteriorelastomer 20 and fourth exterior elastomer 20 a.

In one embodiment, elastomers 20 and 20 a both have a second value ofelastic resilience. The elastomers 10 and 10 a can have a length that isat least the same as that of elastomers 20 and 20 a.

The first layer elastomers 10 and 10 a and the second layer elastomers20 and 20 a can be respectively made of elastic materials havingdifferent values of elastic resilience. The first and second elastomerlayers 10 and 20 and elastomer layers 10 a and 20 a are respectivelycombined to form a two-part spring with a boardside unitary body and aroadside unitary body.

As shown in FIG. 5, boardside and the roadside unitary bodies arecollectively mounted on kingpin 511 of each of the baseplate 91 suchthat one end of each of the two-part control spring 1 and 1 a is setagainst and mates one of two opposite sides of the axle hanger 92 tohave the axle hanger 92 fixed between the combined turning controlspring 1 and 1 a (boardside 1 and roadside la unitary bodies togetherforming control spring) and mounted on the kingpin 511 of the baseplate91.

The combined roadside and boardside turning control spring 1 and 1 afunction to resist, with elasticity thereof, a turning force applied tothe axle hanger 92 due to weight change during skateboarding conductedby a user and provides effects of nonlinear turning control and shockdamping.

In an embodiment, the first layers shown in FIGS. 1A and 1B, 10 and 10 aand the second layer 20 and 20 a are selected from elastic materials andare combined together as a unitary body by means of one of pouring viainjection molding.

In an embodiment, the first value of elastic resilience of the firstlayer 10 and 10 a with a different durometer than the second value ofelastic resilience of the second layer 20 and 20 a so that the firstlayer 10 and 10 a have flexibility higher than that of the second layers20 and 20 a.

In an embodiment, the first value of elastic resilience of the firstlayer 10 and 10 a is higher than the second value of elastic resilienceof the second layer 20 and 20 a so that the first layer 10 and 10 a haveflexibility lower than that of the second layer 20 and 20 a.

In an embodiment, the first value of elastic resilience of the firstlayer 10 and the second value of elastic resilience of the second layerare selected from specification of Shore “A”. More particularly, in anembodiment, a first layer can be chosen from durometers having a rangeof 85 A to 100 A, and a second, softer layer can have durometers rangingfrom 65 A to 95 A.

In an embodiment, the first layer 10 and 10 a and the second layer 20and 20 a are combined as a unitary body with elastic materials ofdifferent colors so that the turning control spring 1 is provided withmultilayers of colors, shows enhanced aesthetics.

In an embodiment, the second layer 20 and 20 a is structured to show anoutside configuration that is of a conic shape or other different shapesto meet the needs for different installation conditions.

In an embodiment, the turning control spring 1 according to anembodiment further comprises a third layer. The third layer has a thirdvalue of elastic resilience. The third layer 30 is combined with anoutside surface of the second layer 20 such that the first layer 10, thesecond layer 20, and the third layer 30, which can be formed of plasticand/or elastic materials, are combined together as a unitary body toexhibit three different values of elastic resilience.

FIGS. 6A, 6B, 6C through 21A, 21B and 21C illustrate differentembodiments illustrating different shapes that can be implemented on aspring in accordance with embodiments. Thus, a variable-rate elastomericsteering control spring in accordance with embodiments can have interiorelastomers of either or both the boardside unitary bodies and theroadside unitary bodies with shapes whose cross-sections consisting ofat least one of the following: hourglass, triangular, rectangular,semi-circular, asymmetric, and rhombus. Each cross-section combinesdifferent durometer elastomers to advantageously provide steeringcontrol, as explained in more detail below.

Referring now to FIGS. 6A, 6B and 6C,a particular implementation of aboardside unitary body 600 shows an interior elastomer with a triangulargeometrically widened area 610 and outer elastomer 620. Likewise, FIGS.7A, 7B and 7C illustrates another implementation of a boardside unitarybody 700 showing interior elastomer semi-circular widening 710, alsoreferred to as a “bulging barrel” cross-section next to outer elastomer720. When a semi-circular area within a spring has a softer durometer, askater beneficially gains control during turns.

FIGS. 8A, 8B and 8C illustrates a triangular geometrically widened area810 on a roadside unitary body 800. Thus, widened interior area 810 andexterior elastomer 820 together form unitary body 800. FIGS. 9A, 9B and9C illustrate the roadside “bulging barrel” cross-section 910 withexterior elastomer 920 to form a roadside portion 900.

FIGS. 6A, 6B and 6C through FIGS. 9A, 9B and 9C illustrate springportions with widened cross-sections that provide a center elastomerthat, in one embodiment, can be of a softer durometer to provide acontrolled variable rate spring profile.

Another embodiment is shown in FIGS. 10A, 10B and 10C combined withFIGS. 11A, 11B and 11C, which shown a boardside unitary body showinginterior elastomer geometric rhombus-like asymmetric cross-section 1010and exterior elastomer 1020 on unitary body 1000; and, in FIGS. 11A, 11Band 11C a roadside unitary body 1100 showing interior elastomergeometric rhombus-like asymmetric widening 1110 and exterior elastomer1120.

In an embodiment, having a narrower softer interior durometer 1010 and1110 asymmetry can enhance vibrational damping.

FIGS. 12A, 12B and 12C illustrate another embodiment of a roadsideunitary body showing interior elastomer geometric rhombus-likeasymmetric widening 1210 and exterior elastomer 1220 of unitary body1200. Unlike FIG. 11C, FIG. 12C shows a wider interior elastomer at thebottom of the roadside unitary body 1200 (the narrowed portion of thefrustrum portion), which provides more stability and control for turnsand unique variable-rate spring properties.

Referring now to FIGS. 13A, 13B and 13C, an embodiment of a boardsideunitary body 1300 shows an interior elastomer geometric triangularcross-section with symmetric narrowing 1310 and exterior elastomer 1320.In one embodiment, the roadside and boardside unitary bodies can be ofdifferent geometries such that an interior geometry 1310 on a boardsideunitary body 1300 is combined with a roadside unitary body 1200 with aninterior cross-section with a rhombus-like asymmetric widening 1210.Such a combination spring can be beneficial for steering at high and lowspeed turns and unique variable-rate spring properties such as asteering resistance profile.

Referring to FIGS. 14A, 14B and 14C a boardside unitary body 1400 showsinterior elastomer with an hourglass symmetric cross-section shape 1410and exterior elastomer 1420 in accordance with an embodiment.

The hourglass symmetric cross-section boardside unitary body 1400 shownin FIG. 14C can be combined with a roadside unitary body 1500 shown inFIGS. 15A, 15B and 15C showing a triangular narrowed interior elastomercross-section area 1510 and exterior cross-section 1520.

In another embodiment, boardside unitary body 1400 shown in FIG. 14C canbe combined with roadside unitary body 1600 shown in FIGS. 16A, 16B and16C, which illustrate a particular implementation of a roadside unitarybody 1600 showing interior elastomer with an hourglass symmetriccross-section area 1610 and exterior elastomer 1620 in accordance withan embodiment of the present application.

Thus, as shown, a variable-rate elastomeric steering control spring indifferent embodiments can have a same cross-section in boardside unitarybody and roadside unitary body or can have different cross-sections.Each skateboard has two skate trucks, a forward and a rear skate truck.Thus, in one embodiment, the forward skate truck and the rear skatetruck have different cross-section interior geometries. Accordingly, themaximum number of different geometries can be four different interiorgeometries, which can be implemented by a skater in a modular fashionaccording to the necessities of the skateboarder.

Referring now to FIGS. 17A, 17B and 17C, another embodiment 1700 isdirected to interior elastomers 1710 that are partially lengthened ascompared to an exterior elastomer. FIGS. 17A, 17B and 17C illustrate aboardside unitary body 1700 showing partially lengthened interiorelastomer cross-section area 1710 and exterior elastomer 1720. FIGS.18A, 18B and 18C illustrate a complimentary roadside unitary body 1800showing partially lengthened bottom end interior elastomer 1810, andexterior elastomer 1820 in accordance with an embodiment. The extendedpartial interior elastomer 1810 beneficially reduces noise at a washercomponent or lock nut coupling a kingpin at the roadside unitary body. Awasher fitting over the extended elastomer can eliminate noise orvibration that could otherwise occur.

Likewise, FIGS. 19A, 19B and 19C illustrate a roadside unitary body 1900showing partially lengthened upper end interior elastomer 1910 andexterior elastomer 1920. As shown, the partially lengthened portion 1910can be either near the bottom of the skate truck, or can be closer tothe board of the skate truck. The partially lengthened portion 1910uniquely enables spring to engage the kingpin with more contact aboutthe kingpin. As shown, the unitary bodies have an extended lengthenedportion on the bottom of a roadside unitary body 1900. In one exemplaryembodiment, the unitary body of FIGS. 17A, 17B and 17C is used togetherwith the unitary body of FIGS. 19A, 19B and 19C. The respectivelengthened interior portions in one embodiment meet in the middle alongan axle hanger thereby taking up space that would otherwise be betweenthe boardside unitary body and the roadside unitary body. For example,the lengthened interior portions can abut from either side inside abushing seat ring of a kingpin. The extension of the interior elastomerthereby limits side-to-side slop of an axel hanger, which can bebeneficial for racing skateboards operating at high gravitationalg-forces.

Referring now to FIGS. 20A, 20B and 20C and FIGS. 21A, 21B and 21C, thecross-section views of the two types of durometers illustrates animplementation of a boardside unitary body 2000 and 2100 with interiorelastomer 2010 and exterior elastomer 2020 with rectangularcross-section and a roadside unitary body showing interior elastomer2110 and exterior elastomer 2120 with rectangular cross-section inaccordance with an embodiment.

It will be understood that each of the elements described above, or twoor more together may also find a useful application in other types ofmethods differing from the type described above.

While certain novel features of this invention have been shown anddescribed and are pointed out in the annexed claim, it is not intendedto be limited to the details above, since it will be understood thatvarious omissions, modifications, substitutions and changes in the formsand details of the device illustrated and in its operation can be madeby those skilled in the art without departing in any way from the claimsof the present invention. While particular aspects of the presentsubject matter described herein have been shown and described, it willbe apparent to those skilled in the art that, based upon the teachingsherein, changes and modifications may be made without departing from thesubject matter described herein and its broader aspects and, therefore,the appended claims are to encompass within their scope all such changesand modifications as are within the true spirit and scope of the subjectmatter described herein. Furthermore, it is to be understood that theinvention is defined by the appended claims.

It will be understood by those within the art that, in general, termsused herein, and especially in the appended claims (e.g., bodies of theappended claims) are generally intended as “open” terms (e.g., the term“including” should be interpreted as “including but not limited to,” theterm “having” should be interpreted as “having at least,” the term“includes” should be interpreted as “includes but is not limited to,”etc.). It will be further understood by those within the art that if aspecific number of an introduced claim recitation is intended, such anintent will be explicitly recited in the claim, and in the absence ofsuch recitation no such intent is present. For example, as an aid tounderstanding, the following appended claims may contain usage of theintroductory phrases “at least one” and “one or more” to introduce claimrecitations. However, the use of such phrases should not be construed toimply that the introduction of a claim recitation by the indefinitearticles “a” or “an” limits any particular claim containing suchintroduced claim recitation to inventions containing only one suchrecitation, even when the same claim includes the introductory phrases“one or more” or “at least one” and indefinite articles such as “a” or“an” (e.g., “a” and/or “an” should typically be interpreted to mean “atleast one” or “one or more”); the same holds true for the use ofdefinite articles used to introduce claim recitations.

In addition, even if a specific number of an introduced claim recitationis explicitly recited, those skilled in the art will recognize that suchrecitation should typically be interpreted to mean at least the recitednumber (e.g., the bare recitation of “two recitations,” without othermodifiers, typically means at least two recitations, or two or morerecitations). Furthermore, in those instances where a conventionanalogous to “at least one of A, B, and C, etc.” is used, in generalsuch a construction is intended in the sense one having skill in the artwould understand the convention (e.g., “a system having at least one ofA, B, and C” would include but not be limited to systems that have Aalone, B alone, C alone, A and B together, A and C together, B and Ctogether, and/or A, B, and C together, etc.).

What is claimed is:
 1. A variable-rate elastomeric steering controlspring for a skate truck, comprising: a boardside unitary body formed ofan exterior first elastomer having a first durometer on the Shore “A”scale, and an interior second elastomer coupled to the first elastomerand extending at least length of the exterior first elastomer, thesecond elastomer having a second durometer on the Shore “A” scale and athrough hole disposed to receive a kingpin of the skate truck; aroadside unitary body formed of an exterior third elastomer having athird durometer on the Shore “A” scale, and an interior fourth elastomercoupled to the third elastomer and extending at least a length of theexterior third elastomer, the interior fourth elastomer having a fourthdurometer on the Shore “A” scale and a through hole disposed to receivethe kingpin; and wherein the first, second, third and fourth elastomerscomprise at least two durometers on the Shore “A” scale between 65 A and100 A to enable the boardside unitary body and the roadside unitary bodyto form the variable-rate elastomeric steering control spring whendisposed on the kingpin of the skate truck.
 2. The variable-rateelastomeric steering control spring of claim 1, wherein the skate truckincludes a seat to receive a distal end of the boardside unitary bodyand a proximal end of the roadside unitary body and allow forcompression of the variable-rate elastomeric steering control spring. 3.The variable-rate elastomeric steering control spring of claim 1,wherein the boardside unitary body has a cylindrical shape and theroadside unitary body has a frustrum shape.
 4. The variable-rateelastomeric steering control spring of claim 1, wherein the interiorelastomers of both the boardside unitary bodies and the roadside unitarybodies have shapes with cross-sections consisting of at least one of thefollowing: hourglass, triangular, rectangular, semi-circular,asymmetric, and rhombus.
 5. The variable-rate elastomeric steeringcontrol spring of claim 4, wherein the shape of the interior elastomerand exterior elastomers functionally affects turning control of theskate truck.
 6. The variable-rate elastomeric steering control spring ofclaim 4, wherein the boardside and roadside interior elastomer shapesprovide a non-linear steering control of the skate truck.
 7. Thevariable-rate elastomeric steering control spring of claim 1, whereinthe first and third durometers are between 85 A and 100 A of the Shore“A” scale.
 8. The variable-rate elastomeric steering control spring ofclaim 1, wherein the second and fourth durometers are between 65 A and90 A of the Shore “A” scale.
 9. The variable-rate elastomeric steeringcontrol spring of claim 1, wherein the first, second, third and fourthelastomers are of four different durometers of between 65 A and 100 A ofthe Shore “A” scale.
 10. The variable-rate elastomeric steering controlspring of claim 1, wherein the boardside unitary body further comprisesa fifth elastomer disposed between the first and the second elastomers,the fifth elastomer having a durometer of between 65 A and 100 A of theShore “A” scale.
 11. The variable-rate elastomeric steering controlspring of claim 1, wherein the roadside unitary body further comprises asixth elastomer disposed between the third and the fourth elastomers,the sixth elastomer having a durometer of between 65 A and 100 A of theShore “A” scale.
 12. A skateboard comprising: a deck; at least two skatetrucks coupled to the deck, each skate truck including: an axle; amounting bracket including a kingpin protruding down from the mountingbracket, the kingpin having a variable-rate elastomeric steering controlspring including: a boardside unitary body formed of an exterior firstelastomer having a first durometer on the Shore “A” scale, and aninterior second elastomer coupled to the first elastomer and extendingat least a length of the exterior first elastomer, the second elastomerhaving a second durometer on the Shore “A” scale and a through holedisposed to receive a kingpin of the skate truck; a roadside unitarybody formed of an exterior third elastomer having a third durometer onthe Shore “A” scale, and an interior fourth elastomer coupled to thethird elastomer and extending at least a length of the exterior thirdelastomer, the interior fourth elastomer having a fourth durometer onthe Shore “A” scale and a through hole disposed to receive the kingpinwherein the first, second, third and fourth elastomers of the boardsideunitary body and the roadside unitary body form the variable-rateelastomeric steering control spring when disposed on the kingpin of theskate truck
 13. The skateboard of claim 12 wherein each of the at leasttwo skate trucks includes a seat to receive a distal end of theboardside unitary body and a proximal end of the roadside unitary bodyand allow for compression of the variable-rate elastomeric steeringcontrol spring.
 14. The skateboard of claim 12 wherein the boardsideunitary body has a cylindrical shape and the roadside unitary body has afrustrum shape.
 15. The skateboard of claim 12 wherein the interiorelastomers of both the boardside unitary bodies and the roadside unitarybodies have shapes with cross-sections consisting of at least one of thefollowing shapes: hourglass, triangular, rectangular, circular,asymmetric, and rhombus.
 16. The skateboard of claim 15, wherein theshape of the interior elastomer and exterior elastomers functionallyaffects turning control of the skate truck.
 17. The skateboard of claim15, wherein the boardside and the roadside interior elastomer shapeprovides a non-linear steering control of the skate truck.
 18. Theskateboard of claim 12 wherein the interior elastomers of both theboardside unitary bodies and the roadside unitary bodies each have alengthened interior elastomer that abut inside a bushing seat ring ofthe kingpin.
 19. An apparatus comprising: a boardside unitary bodyformed of an exterior elastomer having a durometer on the Shore “A”scale of between 65 A and 100 A, and an interior elastomer coupled tothe exterior elastomer and extending at least a length of the exteriorelastomer, the interior elastomer having a durometer on the Shore “A”scale between 65 A and 100 A and a through hole disposed to receive akingpin for attaching the roadside unitary body to a skate truck for askateboard; and wherein the exterior and interior elastomers comprise atleast two durometers on the Shore “A” scale between 65 A and 100 A toenable the boardside unitary body to form a variable-rate elastomericsteering control spring when disposed on the kingpin of the skate truck.20. The apparatus of claim 19 wherein the roadside unitary body isdisposed on the kingpin of the skate truck as part of a variable-rateelastomeric steering control spring, wherein the spring includes: theboardside unitary body; and a roadside unitary body formed of theexterior elastomer and the interior elastomer coupled to the andextending at least a length of the exterior elastomer and having throughhole disposed to receive the kingpin of the skate truck.
 21. Theapparatus of claim 20 wherein the roadside unitary body or the boardsideunitary body is disposed on the kingpin of the skate truck and whereinthe interior elastomers of both the boardside unitary bodies and theroadside unitary bodies have shapes with cross-sections consisting of atleast one of the following: hourglass, triangular, rectangular,semi-circular, asymmetric, and rhombus.